Cap making machines

ABSTRACT

A twin-tool press for a machine for making caps for bottles and other containers from metal foil includes two tool sets for blanking and forming caps from the same strip of foil arranged so that the line between their centers is inclined at an angle of about 60* to the longitudinal axis of the strip. The blanks simultaneously cut by the two tools therefore form two rows down the length of the strip. The two tools sets comprise two punch assemblies carried on a horizontally reciprocating plunger and co-operating, stationary, die assemblies. The metal foil strip is intermittently fed between the assemblies and the plunger is reciprocated so that the assemblies co-operate to effect blanking and forming operations during the periods when the foil is stationary. The caps are retained inside the punches as the plunger retracts after a blanking and forming operation and the punch assemblies include ejector rings for ejecting the caps from within the punches. The ejector ring of the upper punch is arranged to operate subsequently to that of the lower punch so that the two caps, which are formed simultaneously, are ejected successively to reduce the risk of the caps jamming or wedging as they drop down into the mouth of a cap delivery chute.

United States Patent [1 1 Ford et al.

CAP MAKING MACHINES Inventors: Geoffrey Ewart Ford, Bedford;

Philip Sidney Waite, Kempston, both of England Fords (Finsbury) Limited, Kempston, Bedford, England Filed: June 28, 1971 Appl. No.: 157,317

[73] Assignee:

[5 6] References Cited UNITED STATES PATENTS 10/1939 Plumb 113/121 A 8/1941 Wareham 113/121 A 7/1943 Gladfelter 113/120 H 11/1925 Berry 72/351 Primary Examiner-Richard J. Herbst Attorney-l-lolcombe, Wetherill & Brisebois [57] ABSTRACT A twin-tool press for a machine for making caps for June 12, 1973 bottles and other containers from metal foil includes two tool sets for blanking and forming caps from the same strip of foil arranged so that the line between their centers is inclined at an angle of about 60 to the longitudinal axis of the strip. The blanks simultaneously cut by the two tools therefore form two rows down the length of the strip. The two tools sets comprise two punch assemblies carried on a horizontally reciprocating plunger and co-operating, stationary, die assemblies. The metal foil strip is intermittently fed between the assemblies and the plunger is reciprocated so that the assemblies co-operate to effect blanking and forming operations during the periods when the foil is stationary. The caps are retained inside the punches as the plunger retracts after a blanking and forming operation and the punch assemblies include ejector rings for ejecting the caps from within the punches. The ejector ring of the upper punch is arranged to operate subsequently to that of the lower punch so that the two caps, which are formed simultaneously, are ejected successively to reduce the risk of the caps jamming or wedging as they drop down into the mouth of a cap delivery chute.

7 Claims, 1 Drawing Figure PAIENIED JUN 1 2 1915 CAP MAKING MACHINES The present invention relates to machines for making .caps of aluminum or other foil for milk bottles, or other bottles and containers. In such machines the caps are punched by a blanking and forming tool from a strip of foil which is advanced intermittently through the machine, the forrned caps being discharged down a delivery chute to a station where the caps are applied to the bottles or containers. Machines of this type are described in prior British Pat. Nos. 667,301, 756,440 and A saving of foil of approximately 9 percent can be achieved by employing two sets of blanking and forming tools in a press unit punching from the same strip of foil. The line between the centers of the two tool sets is inclined at an angle of about 60 to the longitudinal axis of the strip so that the blanks cut by the two tools form two rows down the length of the strip, the two rows interfitting and thus providing a saving in foil width as above mentioned.

The two tool sets move together and are guided so as to ensure correctalignment of the two punches with their respective dies.

One of the problems which arises with such a twintool press, particularly if the axis of movement of the tools is horizontal, concerns the feeding of the two caps through a collector at the top of the cap delivery chute as there is a risk that the two caps can wedge together at the mouth of the chute.

The present invention consists in a horizontally disposed twin-tool press of the type described above wherein means are provided for delaying ejection of the cap made by the upper of the two tool sets relative to the ejection of the cap made by the lower of the two tool sets.

This may be effected by controlling the ejection of the caps in accordance with the degree of opening of the tools so that as the tools open the cap from the lower tool set will be ejected first, and on further opening of the tools the cap from the upper tool set will then eject. The two caps, which are made simultaneously, are ejected into the collector at successive instants of time and the risk of the caps jamming or wedging is reduced.

In a preferred embodiment delayed ejection is used in the punch, which latter also acts as a forming die and is themoving part of the tool. The formed caps are retained inside the punches until the press unit has partially. opened, whereupon only the cap from the lower punch will be ejected, and on further opening the cap from the upper punch will be ejected.

in order further to ensure that the first cap to be ejected is safely in the chute before the second cap is ejected, an air blast device may be associated with the lower tool set only in order to accelerate the fall of this cap.

Apart from the economy brought about by the foil saving, a twin-tool machine according to the invention need only operate at half the speed of a single tool press;

producing the same number of caps per minute,-and consequently the problems of handling foil strip at high speed are greatly diminished, and the general wear and tear on the whole press mechanism is also reduced.

In order that the invention may be more readily understood, reference will now be made to the accompanying drawing which is a part plan view and part horizontal section through a twin-tool press according to the invention for blanking and forming bottle caps from metal foil strip.

The press comprises a cylindrical sleeve 1 which is arranged in a horizontal position in a cap making ma- ,chine and serves as a guide for a plunger 2. The plunger is prevented from rotating relative to the sleeve by a keyway (not shown) and is reciprocated within the sleeve by means of an eccentric 3 coupled to the plunger by a connecting rod 4 and rotated by means of an electric motor 5 connected to the eccentric in any convenient manner. The plunger carries two punch assemblies 6 (only one of which is shown in the drawing) positioned so that the line through the centers of the assemblies is inclined at an angle of about 60 to the vertical. The end of the sleeve opposite the eccentric 3 is closed by a mounting member 7 carrying two die assemblies 8, 9 arranged to co-operate respectively with the two punch assemblies on the plunger to form the two tool sets.

The two punch assemblies 6 are identical and each includes an annular punch 10 closed at its rear end and secured to the front face of the plunger 2 by means of cap head screws 1 l. Mounted centrally of the punch 10 in an annular retainer 12 is a rubber pad 13 having a backing plate 14, which assists embossing of the bottle cap. The retainer 12 is secured to a spacer member 15, which serves to locate the rubber pad towards the front of the punch 10, by screws 16 and the spacer member 15 is secured to the plunger through the end wall of the punch by a cap head screw 17 which is concealed behind the rubber pad in the central opening of the retainer l2. Disposed in the annular space between the retainer and the punch is an ejector ring 18 which is split axially into two semi-circular parts and is axially slidable on the retainer 12 and spacer 15. The ejector ring is prevented from sliding off the retainer by an an nular shoulder 19 thereon engaging an inward flange 20 around the rear end of the ejector ring. The two-part ejector ring is operated by two push rods 21 which project through the plunger and the end wall of the punch and respectively engage the two parts of the ring. The front ends of the push rods engage the flange 20 of the ejector ring and the push rods are operated by an actuating plate 22 arranged to engage their rear ends disposed within the skirt of the plunger. The actuating plate 22 is supported by a rod 23 slidably mounted in a bearing 24 in an annular back plate 25 secured to the end of the sleeve. The plate is resiliently urged towards the push rods by a compression spring 26 disposed on the rod between the plates 22, 25 and lock nuts 27 screwed onto the end of the rod 23 projecting through the back plate 25 secure the shaft thereto and serve as a stop to limit movement of the actuating plate 22 under the action of the spring. These nuts also enable adjustment of the position at which the actuating plate operates the push rods and, in accordance with this invention, the nuts on the tworods 23 are adjusted so round the punches 10. It is supported in position by two rods (only one of which is shown) projecting from the crown of the plunger. Each rod 30 is slidably mounted in bushes 31 supported in a flanged sleeve 32 projecting through an aperture 33 in the plunger crown and secured in position by cap head screws 34. Each rod 30 has a head 35 at its rear end for maintaining it captive in the sleeve and the clamping plate 28 is secured to its front end by a cap head screw 36 and stepped washer 37, the head of the cap screw being located in a recess 38 in the clamping plate so that it is behind the front face of the clamping plate. The latter is resiliently urged to its position adjacent the front of the punch assemblies by means ofa compression spring 39 located on each rod 30 between the back of the clamping plate and the flanged sleeve 32.

A shear plate 40 is supported inside the sleeve. l by the mounting member 7, to which it is secured by cap head screws 41. It has two circular openings 42 surrounding the front or inner ends of the die assemblies 8, 9 and forming circular shear edges 43. The die assemblies are identical and are both carried on a plate 44 secured to the mounting member 7 over an opening 45 therein by readily releasable screws (not shown) so that the die assemblies may be readily removed outwardly through the opening 45 without affecting the setting of the shear plate 40. Each die assembly 8, 9 comprises an ejector ring 46 slidably mounted on an annular forming die 47 and a central disc member 48 which may have embossing on its front face for producing embossed ornamentation and/or advertising matter on the cap. The ejector ring 46 is fastened to the inner ends of two rods 49 which project through the plate 44 and have their outer ends secured to an annular plate 50 slidably mounted on a tubular member 51 which has its inner end screwed into an aperture 52 in the plate 44. A compression spring 53, disposed on the tubular member between the plate and a knurled nut 54 screwed onto its outer end, resiliently urges the ejector ring 46 to the position illustrated in the drawing with its front end adjacent the shear edge 43. The ejector ring is stopped in this position by an annular shoulder 54 thereon abutting a co-operating annular shoulder 55 on the annular die 47. The latter is secured in position by being screwed onto the inwardly projecting, threaded end of the tubular member 51. The central embossing disc 48 is fixed within the front end of the die 47 by means ofa shaft 56 extending through the center of the tubular member 51 and having a threaded inner end screwed into the back of the embossing disc and a knurled head 57 on its outer end. By turning the knurled head 57 the shaft is screwed into the disc until it is tight against an annular shoulder 58 of the die 47 which supports the back of the disc.

The press tool operates as follows. A strip 59 of metal foil is intermittently fed between the punch and die assemblies, through slots in the top and bottom of the sleeve 1. The plunger 2 is reciprocated within the sleeve and the assemblies co-operate to effect blanking and forming operations during the periods when the foil is stationary. As the plunger 2 advances, the clamping plate 28 first clamps the stationary foil strip against the shear plate 40 and then the punches 10 move relative to the clamping plate and co-operate with the shear edges 43 to stamp-out two caps. Further advance of the punches with the plunger causes them to press back the ejector rings 46 and to form the caps about the forming dies 47. The inner cylindrical surfaces of the punches also serve as forming dies. As the caps are formed, the rubber pads 13 press the caps against the embossing discs 48 to produce the embossing on the capsv Upon retraction of the plunger 2, the caps are removed from the forming dies 47 within the punches l0 and this is assisted by the ejector rings 46 which push the caps off the forming dies 47. As the plunger is further retracted, firstly the ejector ring 18 of the lower punch assembly 6 is operated by its push rods 21 engaging the associated actuating plate 22 and, subsequently, the ejector ring 18 of the upper assembly is operated so that the cap is first ejected from the lower punch and drops down into the collector funnel 60 of the delivery chute 61 followed by the cap from the upper punch.

Whilst a particular embodiment has been described, it will be understood that various modifications may be made without departing from the scope of the invention as defined by the appended claims.

We claim:

1. A twin-tool press for making caps for bottles and other containers from foil strip, comprising two sets of blanking and forming tools, said tool sets being disposed generally horizontally, means for reciprocating the tools of the respective sets relative to one another along generally horizontal axes, means for feeding foil strip in a generally vertical plane between the tools of the sets, whereby two caps are simultaneously formed from the same strip when the tools are closed together, said tool sets being so positioned that the line between their centers is inclined to the longitudinal axis of said strip, and ejector means for ejecting the caps from the tool sets upon opening of the tools, one of said ejector means being adapted to operate subsequently to the other, whereby the caps which are formed simultaneously are ejected successively from the two sets.

2. A twin-tool press as claimed in claim 1, including a generally horizontally disposed sleeve, a plunger slidably guided within said sleeve, means for reciprocating said plunger along a generally horizontal axis within said sleeve, two punch assemblies carried by said plunger, two die assemblies supported by said sleeve and arranged to co-operate respectively with said two punch assemblies to constitute the said two tool sets, and means providing for the feed of said foil strip through said sleeve and between said punch and die assemblies.

3. A twin-tool press as claimed in claim 2, wherein said punch assemblies are also adapted to act as forming dies and the caps are retained within the punch assemblies upon retraction of the plunger away from said die assemblies, and wherein said ejector means are mounted respectively within said punch assemblies and means are provided for respectively actuating said ejector means at different positions along the path of retraction of said plunger.

4. A twin-tool press as claimed in claim 3, wherein each ejector means is operated by push rod means slidably mounted in said plunger, and each actuating means is mounted on said sleeve on the opposite side of said plunger to said punch assemblies in a position to bear on said push rod means during retraction of said plunger.

5. A twin-tool press as claimed in claim 4, wherein each actuating means is movably mounted with respect to said sleeve and spring means resiliently urges said actuating means to the position at which it bears on said push rod means.

6. A twin-tool press as claimed in claim 5, including means for adjusting said position of each actuating means.

7. A twin-tool press as claimed in claim 6, wherein said sleeve is adapted to be horizontally disposed in a cap making machine with the foil strip fed in a vertical direction between said tool sets, and said sets are so positioned that the line joining the centers thereof is disposed at an angle of approximately 60 to the longitudinal axis of said foil strip, and wherein each of said punch assemblies comprises an annular punch projecting from said plunger, support means disposed within said punch and defining an annular space between said support means and said punch, an ejector ring slidably mounted on said support means within said annular space and adapted to eject a cap from within said punch, said ejector ring being axially split into two semi-circular parts, two push rods projecting through said plunger and having ends disposed within the punch arranged to bear respectively on said two parts of said ejector ring, a back plate secured to said sleeve at the end thereof adjacent the opposite ends of said push rods, rod means supported by said back plate and slidable axially of said sleeve, an actuating plate supported by said rod means in a position to bear on said opposite ends of said push rods during retraction of the plunger to effect operation of said ejector ring through said push rods, compression spring means disposed on said rod means to resiliently urge said actuating plate into said position, and adjustable stop means secured to said rod means on the opposite side of said back plate to said spring means to attach said rod means to said back plate and define said position, said stop means being adjusted to position said actuating plate associated with the upper punch assembly rearwardly of that associated with the lower punch assembly. 

1. A twin-tool press for making caps for bottles and other containers from foil strip, comprising two sets of blanking and forming tools, said tool sets being disposed generally horizontally, means for reciprocating the tools of the respective sets relative to one another along generally horizontal axes, means for feeding foil strip in a generally vertical plane between the tools of the sets, whereby two caps are simultaneously formed from the same strip when the tools are closed together, said tool sets being so positioned that the line between their centers is inclined to the longitudinal axis of said strip, and ejector means for ejecting the caps from the tool sets upon opening of the tools, one of said ejector means being adapted to operate subsequently to the other, whereby the caps which are formed simultaneously are ejected successively from the two sets.
 2. A twin-tool press as claimed in claim 1, including a generally horizontally disposed sleeve, a plunger slidably guided within said sleeve, means for reciprocating said plunger along a generally horizontal axis within said sleeve, two punch assemblies carried by said plunger, two die assemblies supported by said sleeve and arranged to co-operate respectively with said two punch assemblies to constitute the said two tool sets, and means providing for the feed of said foil strip through said sleeve and between said punch and die assemblies.
 3. A twin-tool press as claimed in claim 2, wherein said punch assemblies are also adapted to act as forming dies and the caps are retained within the punch assemblies upon retraction of the plunger away from said die assemblies, and wherein said ejector means are mounted respectively within said punch assemblies and means are provided for respectively actuating said ejector means at different positions along the path of retraction of said plunger.
 4. A twin-tool press as claimed in claim 3, wherein each ejector means is operated by push rod means slidably mounted in said plunger, and each actuating means is mounted on said sleeve on the opposite side of said plunger to said punch assemblies in a position to bear on said push rod means during retraction of said plunger.
 5. A twin-tool press as claimed in claim 4, wherein each actuating means is movably mounted with respect to said sleeve and spring means resiliently urges said actuating means to the position at which it bears on said push rod means.
 6. A twin-tool press as claimed in claim 5, including means for adjusting said position of each actuating means.
 7. A twin-tool press as claimed in claim 6, wherein said sleeve is adapted to be horizontally disposed in a cap making machine with the foil strip fed in a vertical direction between said tool sets, and said sets are so positioned that the linE joining the centers thereof is disposed at an angle of approximately 60* to the longitudinal axis of said foil strip, and wherein each of said punch assemblies comprises an annular punch projecting from said plunger, support means disposed within said punch and defining an annular space between said support means and said punch, an ejector ring slidably mounted on said support means within said annular space and adapted to eject a cap from within said punch, said ejector ring being axially split into two semi-circular parts, two push rods projecting through said plunger and having ends disposed within the punch arranged to bear respectively on said two parts of said ejector ring, a back plate secured to said sleeve at the end thereof adjacent the opposite ends of said push rods, rod means supported by said back plate and slidable axially of said sleeve, an actuating plate supported by said rod means in a position to bear on said opposite ends of said push rods during retraction of the plunger to effect operation of said ejector ring through said push rods, compression spring means disposed on said rod means to resiliently urge said actuating plate into said position, and adjustable stop means secured to said rod means on the opposite side of said back plate to said spring means to attach said rod means to said back plate and define said position, said stop means being adjusted to position said actuating plate associated with the upper punch assembly rearwardly of that associated with the lower punch assembly. 